Affinity chromatography may be used for the purification of proteins, for example IgG purification. Affinity chromatography media typically comprise a solid support (e.g. a resin) and, attached thereto, a selection of affinity ligands. The selectivity of the ligands typically depends on a number of factors, for example the pH or ionic strength of the sample undergoing separation. The ionic strength or pH may be varied to enhance selectivity for a particular protein.
2-Aminobenzimidazole (ABI) and aminomethylbenzimidazole (AMBI) are examples of affinity chromatography ligands.
Judicious selection of the solid support, ligands and separation conditions allow a reasonable degree of specificity to be attained. However, conventional non-affinity chromatographic processes are typically accompanied by a high degree of non-specific binding. There remains a need for chromatography media having a greater degree of selectivity, particularly towards proteins such as IgG.